Identifying a bath-induced bose liquid in interacting spin-boson models.

Area of Science:

• Condensed Matter Physics
• Quantum Many-Body Systems
• Open Quantum Systems

Background:

• The study of interacting bosonic systems is crucial for understanding quantum phases of matter.
• Spin-boson models are fundamental for describing quantum systems coupled to a bath.
• Generalizing these models to interacting systems reveals new emergent phenomena.

Purpose of the Study:

• To investigate the ground state phase diagram of a 1D hard-core bosonic model with nearest-neighbor interactions coupled to a reservoir.
• To explore the possibility of bath-induced phases in interacting quantum systems.
• To generalize spin-boson models to interacting spin-boson systems.

Main Methods:

• Utilized quantum Monte Carlo simulations to analyze the ground state phase diagram.
• Studied a one-dimensional hard-core bosonic model with nearest-neighbor interactions (XXZ model).
• Coupled each site ohmically to an independent and identical reservoir.

Main Results:

• Identified a novel bath-induced Bose liquid phase away from half filling.
• This Bose liquid phase is compressible, gapless, and conducting, but not superfluid.
• At half filling, a Luttinger liquid and a charge density wave phase were observed.
• The phase transition at half filling is of Kosterlitz-Thouless type with a nonuniversal Luttinger parameter.

Conclusions:

• The coupling to a bath can induce exotic phases in interacting bosonic systems.
• The quantum Monte Carlo method is versatile for studying open quantum systems across various dimensions and parameters.
• This work provides a framework for understanding dissipation effects in complex quantum models.